| 摘要 |
PURPOSE:To stabilize operating pressure by annealing after press-forming a safety cover manufactured by means of press-forming a part of a metal plate. CONSTITUTION:A safety cover A for a sealed storage battery is manufactured in such a way that a pressed part 1a compressed to about half thickness in a shape of circular is formed in the center of one side in a disc metal plate 1 such as nickel or steel and a nonpressed part 1b is formed in its periferal part. After forming the pressed part 1a and nonpressed part 1b, the safety cover is annealed with a reducing or inert gas atmosphere furnace at 700-900 deg.C for about 15min. Thus, the pressed part 1a is converted into an annealed metal structure part 1a having a relatively large grain size. |
